The research proposed is to isolate and characterize human leukemia associated antigens which are being specifically defined serologically by simian and rabbit antisera. The antigens will be used to elicit new antisera, develop new and more sensitive in vitro assays for humoral and cellular immunity in leukemia patients. The antisera will be further evaluated as diagnostic, prognostic and perhaps therapeutic reagents in the detection and management of the various histological types of human leukemia.